The present invention relates to a frame for an adjustable bed of the type having provision for adjustment of the inclination of either or both of the head portion and foot portion of the bed.
Adjustable beds of the described type have long been recognized as being helpful in relieving muscle tension and fatigue. Also, by permitting the separate adjustment of the inclination of the head portion and the foot portion, the user is able to configure the bed to best meet the individual comfort needs of his or her body. A bed of this general type is illustrated for example in U.S. Pat. No. 4,381,571 to Elliott.
In one known frame for a bed of the described type, an actuating mechanism is provided wherein a drive motor acts to move a lever arm, and the lever arm pivots at a pivot point to raise or lower the head or foot portion of the bed. In another known design, a scissors mechanism is employed for this purpose. While these prior designs are satisfactory in many respects, they are typically unable to reliably support and move the movable portion of the bed against a large resistance, as would be present for example when the bed is used by an overweight person, since the torque to raise or lower the movable portion is transmitted directly through the drive motor.
It is an object of the present invention to provide an adjustable bed frame which avoids the above noted limitations and disadvantages of the existing designs.
It is a more particular object of the present invention to provide an adjustable bed frame wherein the frame utilizes mechanical components for supporting the weight of the user in the raised position of the movable portions, and so that the force of this weight is not transmitted through the drive motor.
It is another object of the present invention to provide a lifting mechanism for an adjustable bed which is smoothly and quietly operable, and which provides assurance to the user of its safe and reliable operation.
It is also an object of the present invention to provide a lifting mechanism for an adjustable bed of the described type and wherein the mechanism self releases in the event of an interference or blockage during its lowering movement, to thereby avoid the risk of serious injury to the occupant or other person resulting from the entrapment of a body member in the components of the mechanism.
It is still another object of the present invention to provide a lifting mechanism for an adjustable bed frame which is of simple and inexpensive construction, and which provides a pleasing aesthetic appearance.